Increasing population and the need for security associated with governmental activities and corporate research and development, has prompted various employee and affiliate identification techniques. For example, in larger corporations and governmental institutions, it is common for employees to wear picture ID cards. It is also increasingly common for such individuals to carry machine-readable "keys" wherein some scanning device scrutinizes a visual or magnetic code associated with a pocket-sized card or plate in order to limit access to restricted areas. Such machine-readable devices have the added advantage that comings and goings may be monitored automatically, often by means of a centralized network.
Picture-type ID cards are likewise very popular and have been in existence for much longer than computer-readable identification instruments. Driver licenses are an obvious and ubiquitous example of a typical picture-type ID card, though numerous other examples exist such as those associated with academic and education systems.
Despite the technique used, the unscrupulous are always prepared to devise ways to undermine the system in order to gain access to unauthorized information, privileges or other valuable materials. It is not uncommon, for example, for picture-type ID cards to be tampered with by supplanting certain of the imprinted visual or textual information, thereby creating a bogus version. Indeed, a number of individuals and organizations are in the business of producing such cards.
Identification cards and systems can maintain their integrity only if they are more difficult to compromise than thieves are clever. As such, techniques are increasingly being implemented to render the falsification of ID cards and the like more difficult. These approaches may take two broad forms. One such form involves card manufacturing techniques which make duplication more difficult. The other form generally concerns encoding data so that it is either readable only by a machine or in one way or another more difficult for a human being to perceive or duplicate.
In terms of more sophisticated manufacturing, various layering and/or lamination techniques are now common, the tampering of which would be more obvious to authorized personnel. As for encoding, machine-readable areas are now being included on credit cards, and so forth. For example, the typical Visa or MasterCard now includes a magnetic stripe with encoded identification and account information, as well as a holographically produced image, the combination of which further improves security.
However, even with machine-readable codes and manufacturing techniques which are increasingly impervious to duplication, there remains a need for an identification system for cards and the like which further ensures authenticity by providing a tighter link between the data present in different forms on the card or other ID instrument. For example, even though certain sections of an ID card may contain computer-readable information while other sections contain human-recognizable visual and/or graphical information, in most cases, the two forms of information are substantially independent. As such, one or more of these independent areas may be falsified, thereby facilitating a security breach.